Yarn wrap eliminator



Dec. 7, 1954 L T WYERS, JR 2,696,023

YARN wRA ELIMINATOR Filed Sept. 14, 1951 2 Sheets-Sheet l INVENTOR.

ATTORNEY.

DGC- 7, 1954 l.. T. wYERs, JR

YARN WRAP ELIMINATOR 2 Sheets-Sheen'J 2 Filed Sept. 14, 1951 INVENTOR. TIM@ Mlfyellgdf A TTORNE Y.

Larkin United States Patent O YARN WRAP ELIMINATOR Larkin Talmadge Wyers, Jr., Camden, S. C., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware Application September 14, 1951, Serial No. 246,569

6 Claims. (Cl. 28-22) This invention relates to a device for preventing wraps of yarns, filaments, strands, ribbons or the like, on rollers of a warp treating machine. The invention also provides means for temporarily taking up running ends of yarn, or the like, prior to passing the ends to a subsequent processing step.

Running ends of yarns, filaments, strands, ribbons, or the like, in the form of a warp sheet are frequently processed during the running in different ways. It is sometimes advantageous to break the continuity of the several processing steps during the Stringing-up of a new position and to continue the yarn or the like through a subsequent step only after one step in the process is running satisfactorily. Multiple end processing is desirable from the standpoint of production economy and uniformity of results. But a broken yarn end, or the like, frequently causes a wrap on one of the advancing rollers or causes adjacent ends to tangle, break and/or form additional wraps. Since wraps tend to destroy the advantages of the warp sheet process, steps must be taken to avoid them.

The instant invention is concerned with a temporary take-up means to be used between processing steps and with a means to preserve efficiency of operation by automatically recovering broken ends before a wrap on a roller develops and before interference with other yarns in the warp sheet occurs.

It is, therefore, an object of this invention to provide an improved yarn take-up device from which the yarn end can be picked up readily and carried to the next succeeding step in the process. It is another object to provide a protective device to take up automatically any broken or loose ends passing thereby. Further objects are to prevent entanglement of a broken end with other running ends, to prevent roller wraps and to prevent accumulated waste within the field of processing. Other objects will be apparent from the description that follows.

The objects of this invention are accomplished by means of a suction take-up nozzle connected, through a conveyor tube and a waste yarn collecting chamber, to an aspirating device. The intake end of said nozzle is so arranged as to cause the air to flow co-current and counter-current to the travel of the warp sheet. This pattern of air flow along with sucient velocity gives positive pick-up of broken ends. In addition, the cocurrent air flow puts tension on the ends and when a break occurs this flow prevents the end from slipping on the roll. The suction nozzle is normally mounted above the warp sheet and a confining plate is placed in juxtaposition with the nozzle but below the warp sheet. The invention is further described below.

Figure l is a general showing in side elevation of warp sheet of yarns passing from one processing step to another and the positioning of the automatic protective device of this invention.

Figure 2 is a front elevation of the nozzle part of this device.

Figure 3 is a side elevation of the nozzle part of this device.

d Figure 4 is a top elevation of the nozzle part of this evice.

Figure 5 is an enlarged view of the lower portion of Figure 3.

Figure 6 is an alternative form and arrangement of the protective device of this invention.

With reference to Figures 1 and 6, a warp sheet 1 of yarns passes from rollers 2 and 3 to and beyond roller ICC guide 5 to rollers 4 and 6. At rollers 2 and 3 one processing step is performed and at rollers 4 and 6 another step is normally taken. Between these steps is located the device 7 of this invention comprised of an upper suction nozzle 8 and a lower confining plate 9 between which the yarn warp sheet 1 normally runs. The suction nozzle is joined by a pipe connection 10 to a suitable waste yarn collecting chamber 11 which in turn is connected by pipe 12 to an aspirating device 13. A comb guide 14 and a finish applicator 15 are usually provided. These may be omitted if desired, or additional auxiliary guiding or treating means may be used. The flow of air to the nozzle is indicated by small arrows. Between the nozzle 8 and lower plate 9 the air ow is both co-current and counter-current to the travel of the warp sheet.

In Figures 2 to 5 the nozzle 8 is shown in detail. It comprises two main housing members 16 and 17 bolted together along the side edges and spaced by means of a gasket 18. The front and back flanges or lips 19 and Ztl are mounted at the desired angle (or the lips may be normal to the center plane of the air passage, see Figure 6) so that when the assembly is completed the path of the warp sheet is substantially parallel to the outer face of the two lips. The entrance of the nozzle opening 2l, i. e., the space between the lips, is tapered at 25 to an opening at the face of the lips of about three or four times the width of the opening immediately above the lips. The lips 19 and 20 are each rigidly joined as by welding to the two end brackets 22 and 23 which in turn are clamped to the housing members by bolts 24 as shown.

The two nozzle lips extend the full width of the warp sheet and in each direction from the center line of the air passage 21 the lips extend about 11/2 inches or more. In cooperation with the air passage and nozzle lips, the confining plate 9 also extends over a similar area and is spaced from the nozzle lips to provide ample free passage for the warp sheet therebetween. The spacing may be 1A inch, or more or less, depending on the size and spacing of the yarns making up the warp sheet and the specific design of the nozzle. In any event the arrangement is such as to cause air to ilow along the warp sheet, toward the nozzle opening from two directions and such that each end in the warp is in the eld of operation of the device. The vacuum inside the nozzle (the measure of the total air flow at any gap setting) is directly related to the required gap setting. Normally, approximately fifteen inches of water vacuum in the nozzle with a gap setting of three-eights inch is used, but this can be varied rather widely, depending upon yarn denier and other factors.

In operation when all positions are strung in or the warp sheet is full, the warp of yarns passes through the automatic protective device of this invention as shown in Figure 1 and the suction causes air to ow co-current and counter-current to the warp as shown by the arrows. Due to the tension normally existing on the yarn ends there is no yarn contact with the suction device but should an end break beyond this device, the broken end will be picked up by the suction nozzle 8 because the counter-current and co-current air streams acting on the loose end present the yarn to the mouth of the nozzle. In contrast with this when previously available devices were used, the broken end would generally fall away from the suction nozzle and eventually be wound up as a wrap on one of the rollers.

When a new position is being started the yarn end on the roller 3 is brought to the suction nozzle 8 and allowed to be taken up there until uniform treatment of the yarn on rollers 2 and 3 is assured. Then the end is picked up from the nozzle and passed on to the next subsequent processing step. If during the Stringing-in of this subsequent step a break occurs, the nozzle 8 will automatically retrieve the yarn end. It is unnecessary to restring through the entire processing apparatus as was frequently necessary heretofore.

The apparatus of this invention can be used in handling filaments running singly or in a warp sheet. The filaments may be derived from polymeric materials, synthetic or natural.

It is particularly useful in handling`v yarns in the form of a warp, the yarns being of various denier and derived from such polymers as thepolyamides, polyacrylonitriles, cellulose and other similar materials. The co-current and counter-current air flow eliminates the necessity of providing equipment for throwing the yarn to the vsuction nozzle. The air flow gives positive pick-up of 'a broken'end and the positive tension which is placed'on the broken'ends by the co-current air flow prevents the vendfronrslippingon the roll.

Anydeparture from the. above description which conforms to the present invention is intended to be `included within the scope'of the claims.

I claim:

1. Apparatus for directing filaments out of their normalfpath of vtravel whicheomprises a suction nozzle composed of two housings which are separated by a spacer and which are shaped-to provide a passage yllorair and said filaments and whichhas flanges at the entrance end; and in juxtaposition to said flanges a confining plate, the faces of said flanges and confining plate being closely spaced and of similararea and approximately in parallel relationship.

2. Apparatus in accordance with claim l in which the entrance end of said nozzle is tapered.

3. Apparatus in accordance with claim 1 in which the confining plate is spaced in respect to the said .nozzle to provide for passage of said filament traveling in said normal path between and beyond said nozzle and said confining plate.

4. Apparatus in accordance with claim l in which the confining plate is spaced in respect to the said nozzle to provide for co-current and 4counter-current flow of air to said nozzle in respect to said filament running in said normal path between and beyond said nozzle'and'confining plate.

5. Apparatus for directing filaments out of their normal path of travel which comprises a suction nozzle and in juxtaposition to said nozzle a confining plate, the said positioning being such to permit the laments to run normally between and past said nozzle and said plate and when broken to be directed into said suction nozzle and the faces of the said nozzle and said plate being of similar area.

6. Apparatus in accordance with claim 5 which includes a filament collection chamber connected to said gozzle and an asprating device connected to said cham- References Cited in the file of this patent UNITED STATES PATENTS Number Name 'Date 2,481,197 Caille Sept. 6, 1949 2,634,491 McDermott Apr. 14, 1953 FOREIGN PATENTS Number Country Date 54,397 Austria July 10, 1912 97,847 Switzerland Aug. 9, 1921 268,504 Switzerland Nov. 1'3, 1948 195,511 Germany Feb. 17, 1908 553,074 Great Britain May 6, 1943 652,661 Great Britain Apr. 25, 1951 851,546 France Oct. 2, 1939 

